Do you need to Network? you do not need if you only want to connect to the net with all three comps.
Hears how with 3Com. First you should connect both computers by Ethernet cables if they are near together, if not connect one with the cables supplied, Now start IE and type in the address bar click here hear 192.168.1.1 I have put "Space hear" so it will not be changed in PCA forum to a click hear this should not be in the address bar. then press enter it will bring up the setup page type admin press enter and you are into the setup page. you have then got to enter your IP details like User Name and Password in appropriate boxes. See how you get on first with the above.